The Whites signed the 21-year-old Bulgarian from Barcelona's youth programme but he is yet to make a senior appearance for them.
Temenuzhkov joined La Nucia on loan in January 2020 but the season was ended prematurely by the Covid-19 pandemic.
He scored three goals in 19 Segunda Division and despite saying he intended to return to England to fight for his place, he will be back in the Basque Country next season.
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